Health Effects of Added Sugars

More and more we are finding out that increased added sugars in our diets, coming from the large amount of sugar sweetened beverages and processed foods we consume in the United States, is leading to increased numbers of overweight, obesity and many chronic diseases.  In part 1 of my sugar series- The Truth About Sugar!, I discuss how to determine the difference between an added sugar and a natural sugar.  In this article, part 2 of the sugar series, I discuss the health effects that these added sugars are having on our population. 

1-   Too much added sugar intake is addictive and contributes to overweight and obesity

According to the Centers for Disease Control (CDC), the percentage of children with obesity in the United States has more than tripled since the 1970s with one in five school-aged children having obesity (3).  This is not secluded just to children as 36.5% of U.S. adults have obesity.  Although high added sugar intake alone is a risk factor for many chronic diseases, being obese is also a risk factor for heart disease, stroke, type 2 diabetes and certain types of cancer.

As mentioned in my previous post, The Truth About SUGAR!, Americans consume on average 22 teaspoons of added sugar a day (almost 100 pounds of added sugar a year!).  This does not include the healthy natural sugars that come from fruits, vegetables, grains, and dairy products but only the sugar that has been processed and added to our food supply.  Consuming this much added sugar in our diets contributes an abundance of extra empty calories to our daily intake.  The sugar that we consume from our natural food supply provides us with not only carbohydrates to supply energy to our bodies, but with fiber, vitamins, minerals, and phytochemicals, in addition to other macronutrients, like protein and fat found in that same food item, all contributing to disease prevention.  Consuming whole natural foods that provide fiber, fat and protein contribute to the feeling of satiety or feeling full so that you do not continue to eat only 20 minutes after devouring that sugar laden meal.

So in general, added sugar gives you calories but no added nutrients while natural sugar, coming from fruit or milk for example, are less concerning because of the presence of disease fighting compounds like fiber, vitamins, minerals and macronutrients, that provide your body with the components it needs to keep it running while keeping you feeling fuller longer.  

So why do American’s consume so much sugar when we know how bad it is for us?  Well one answer is that sugar can become highly addictive.  Fructose, one type of simple sugar, can fool your metabolism by impairing your body’s ability to regulate your appetite.  It does this by affecting the hormones ghrelin and leptin.  Ghrelin is responsible for letting the brain know when you are hungry-  sugar affects the suppression of this hormone so that the brain does not turn off your appetite.  Leptin helps your body feel full and stay full, a sensation known as satiety. Interference with these two hormones can lead to over consumption of food and in turn obesity.  Another way that sugar contributes to becoming addictive, is that it can cause massive dopamine release and reduces dopamine signaling in the brains reward center so that we do not get as much pleasure from the food we consume, making us want to consume more (5, 8, 12, 24, 25).

2-  Too much added sugar can lead to Non-Alcoholic Fatty Liver

When you consume carbohydrates in any form, the body breaks them down into the “simple sugars”, glucose, fructose, and galactose.  Fructose, naturally found in fruit and honey, can only be metabolized by the liver.  When we consume fructose from fruit and honey it is not a problem because the amount of fructose we are consuming is not a large amount and can be handled by the liver with no problem.  If we consume fructose in the form of high-fructose corn syrup it can overload the liver turning fructose to fat and over time leading to non-alcoholic fatty liver disease (13,14).  There is a large misconception that fruit is unhealthy because it is providing the body with the simple sugar fructose, but that is not the case.

Fruit is mother nature’s way of providing us with energy in the form of carbohydrates and an abundance of nutrients as well. 

When we chemically alter fructose into high-fructose corn syrup is where the problem beings.  In addition, it’s not like we are consuming a small amount of high fructose corn syrup but instead it is found in almost all our processed foods.  It is also found in a large amount in pop.

To put this into perspective, non-alcoholic fatty liver disease is the same disease you get from excessive alcohol intake but instead you get it from excessive added sugar intake. This is because the liver processes sugar in a similar way it processes alcohol.  Studies are now showing that excess added sugar in the diet can lead to liver toxicity and may increase the risk for several of the same chronic conditions that alcohol was responsible for (8).

3-  Increased added sugar intake contributes to Cardiovascular disease more than saturated fat does!

We have heard it a million times, reduce the fat in your diet to protect your heart.  Now we know that added sugar in our diets can contribute even more to our heart disease risk than saturated fat! This was demonstrated even further with the release of the 2015-2020 dietary guidelines recommending a reduced intake of added sugars in our diet.  A study published in JAMA found that getting too much added sugar in your diet could significantly increase your risk of dying from cardiovascular disease.  In this study, those who got 17-21% of calories from added sugar had a 38% higher risk of dying from cardiovascular disease compared to those who consumed 8% of their calories from added sugar (1).  Over the course of 15 years, another study found the odds of dying from heart disease rose in tandem with the percentage of sugar in the diet- and that was true regardless of a person’s age, sex, physical activity level and body-mass index (29 ). Additional studies have linked the high amount of added sugar in sugar sweetened beverages to be associated with a higher risk of heart disease in both men and women (27.30).   How does sugar actually affect your heart?  Sen et al., found that sugar can actually affect the pumping mechanism of your heart increasing the risk for heart failure (2).  In addition to affecting the pumping mechanism of the heart, studies show that large amounts of fructose can raise blood triglyceride and LDL levels, raised blood pressure, raised blood glucose and insulin levels and increase abdominal obesity in as little as 10 weeks! (26,27,28,29, 31, 32, 33,34).  Due to all of these studies, The American Heart Association recommends no more than 6 teaspoons or 100 calories a day of added sugar for most women and no more than 9 teaspoons or 150 calories a day of added sugar for most men.

4-  Increased added sugar in the diet contributes to Inflammation, Metabolic Syndrome, and Diabetes

We all know that when we hurt ourselves – you break something, you cut yourself, you get a black eye- we can get inflammation in the area we hurt.  This inflammation is considered good inflammation and is accompanied by redness, warmth and swelling.  This is your body’s mechanism to protect itself and heal.  This type of inflammation is considered acute-meaning when the body heals the cut, burn, or broken bone the inflammation will go away.   Did you know that there is a type of bad inflammation?  The bad inflammation is considered chronic inflammation- meaning it may not go away as easily.  This inflammation also doesn’t appear as the acute inflammation and may not be as easy to recognize.  Chronic inflammation presents itself differently in everyone such as presenting as heart disease, obesity, acne, arthritis, bowl disorders, rashes etc.  Chronic inflammation is especially dangerous because we do not know it is happening but it is silently and slowly hurting our healthy body tissues.  Although many factors can contribute to chronic inflammation in the body including stress, smoking, lack of sleep and antibiotics, our diet can highly contribute to or prevent inflammation in the body.  In addition, many factors in our diet can contribute to inflammation with one of the big dietary contributors being added sugars.  Reducing the amount of added sugar in the diet can help tremendously to decrease inflammation within or bodies in turn allowing your body to run smoothly and decrease risk for many chronic diseases.

Metabolic syndrome is a cluster of symptoms including increased blood pressure, high blood sugar, excess body fat around the waist, and abnormal blood cholesterol and triglyceride levels.  Metabolic syndrome is linked to overweight, obesity, physical inactivity and insulin resistance.  One classic sign of metabolic disease is abdominal obesity.  A study done in children found that excess fructose intake caused visceral fat cells (the fat stored around your organs) to mature, setting children up for that abdominal obesity in adulthood and putting them at a higher risk for not only metabolic syndrome but also for heart disease and diabetes (4).  If left uncontrolled, metabolic syndrome can lead to type 2 diabetes and cardiovascular disease.  Added sugar has been shown to lead to metabolic syndrome not only by leading to overweight and obesity but also by inhibiting insulin and causing insulin resistance.  Insulin resistance is not only connected to metabolic syndrome but also diseases associated with metabolic syndrome such as diabetes and cardiovascular disease as well (8,9, 15,16,17).

Diabetes has already been mentioned but to talk about that alone for a minute.  When discussing metabolic syndrome, one of the symptoms was insulin resistance.  Prolonged insulin resistance can progress to type 2 diabetes.  Studies have shown that a major contributor to this are sugar sweetened beverages (which are sweetened with high fructose corn syrup). One study showed people who drink sugar sweetened beverages have up to an 83% higher risk of type II DM (18).

5-  Increased added sugar in the diet can contribute to increased risk of certain types of Cancer

Multiple studies have been done that show those who consume a large amount of added sugar in their diets are at a higher risk of getting certain types of cancer such as colorectal and breast cancer (6,7,19,20,21,22,23).  The thought is that insulin, whose job is to take sugar from the blood after a meal to the target tissues, has a role in the development of these cancers.  From these studies, scientists believe that having a constantly elevated insulin level as a consequence of a high sugar diet can be a contributor to cancer.  Another factor for the development of cancer is inflammation, which added sugar also plays a large role in.  In addition to sugar being a risk factor on its own for cancer, some of the consequences of a high sugar diet are also risk factors for cancer development such as obesity.  In addition, obesity and physical inactivity can also influence insulin levels.

So what should you do to prevent the ill effects of added sugars in your diet?  Reducing intake of processed foods is the number one way to limit the added sugars found in our diets.  Eating natural sugar- that which is found in fruits, vegetables, and whole grains- provides us with carbohydrates to provide our bodies with energy but also vitamins, minerals and phytochemicals that aid in thousands of body processes.  Changing your diet to fuel your body rather than to provide us with the satisfaction of tasting good will not only make you look better but feel better as well.

Stay tuned for part 3 in the sugar series!

References:

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